Summary
| Direction in PACVS | ↑ Elevated — higher than in the comparison group |
|---|---|
| Category | Serologic |
| Also described as | Vaccination exposure marker |
| Compared against | Pre-vaccination baseline |
| Associated symptoms | Confirms vaccine exposure |
| Test type | Blood test (serum / plasma / whole blood) |
| Source | Federico 2024 — doi:10.3390/vaccines12111281 |
| Condition atlas | PACVS Biomarker Atlas |
Trials, interventions and tests
In clinical-trial registrations this marker maps to the outcome term Changes in cellular anti-SARS-CoV-2 immunity associated with PE in subjects with PCC by the determination of SARS-CoV-2 specific igG (8 registered trials use a matching outcome measure).
Clinical trials using Anti-Spike (Anti-S) antibodies as an outcome
- NCT06928272: Long Covid (LC)-REVITALIZE - A Long Covid Repurposed Drug Study (Recruiting)
Outcome measure: General participant reported severity of post-exertional malaise (PEM) using the FUNCAP27 questionnaire - NCT05576662: Paxlovid for Treatment of Long Covid (Completed)
Outcome measure: Change in 1-minute Sit-to-stand Test - NCT05539950: Cardiopulmonary Rehabilitation in Post-acute COVID-19 Syndrome (Withdrawn)
Outcome measure: Changes in 6 minutes walking test (6MWT) - NCT05618574: Nitrite Supplementation in Long COVID Patients (Completed)
Outcome measure: Short Performance Physical Battery (SPPB) - NCT05445674: Plasma Exchange Therapy for Post- COVID-19 Condition: A Pilot, Randomized Double-Blind Study (Completed)
Outcome measure: Changes in cellular anti-SARS-CoV-2 immunity associated with PE in subjects with PCC by the determination of SARS-CoV-2 specific igG - NCT05531019: COVID-19 Sequelae: Treatment and Monitoring. A Dietary Supplement Based on Sea Urchin Eggs With Echinochroma A (Completed)
Outcome measure: Change in the memory over time-points ) baseline, 4 weeks, 8 weeks, 12 weeks) via Rey Auditory Verbal Learning Test. - NCT07182578: Programming Aquatic Therapy for POTS (Completed)
Outcome measure: Heart Rate - NCT07621068: Hyperbaric Oxygen Therapy for Chronic Fatigue Syndrome (CFS) (Not Yet Recruiting)
Outcome measure: Body Composition
Interventions studied alongside this marker
Hypothesis-generating links from trial outcome usage and literature co-occurrence. Not treatment recommendations.
- Ritonavir — 1 trial, 1 PubMed co-citations
e.g. Does Nirmatrelvir/Ritonavir Influence the Immune Response against SARS-CoV-2, Independently from Rebound?
Commercial test availability
SARS-CoV-2 Spike Antibody — commercial laboratory test.
Links are for reference only; availability, specimen requirements and coverage vary by location.
Related Serologic markers in PACVS
Full list: PACVS Biomarker Atlas.
Frequently asked questions
Is Anti-Spike (Anti-S) antibodies high or low in PACVS?
Elevated. Studies summarised in the OSMF atlas report higher Anti-Spike (Anti-S) antibodies in PACVS than in Pre-vaccination baseline. Source: Federico 2024.
What symptoms is Anti-Spike (Anti-S) antibodies associated with in PACVS?
The cited literature associates this marker with Confirms vaccine exposure. These are population-level associations and do not mean the marker causes the symptoms.
Which test measures Anti-Spike (Anti-S) antibodies?
It is measured as a blood test (serum / plasma / whole blood). Commercial laboratories such as Quest Diagnostics, LabCorp list an orderable assay.
Is one abnormal Anti-Spike (Anti-S) antibodies result diagnostic of PACVS?
No. No single biomarker is diagnostic of PACVS. Anti-Spike (Anti-S) antibodies findings come from group comparisons, overlap considerably between patients and controls, and vary with study design, timing and comparison group. A result should be interpreted by a clinician alongside symptoms, history and other tests.
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Last reviewed: 2026-06-30 · Page generated from pacvs.json · Browse: PACVS atlas · Biomarker Index · All marker pages
Disclaimer: This page is an educational synthesis of published, peer-reviewed research and is not medical advice. Biomarker findings vary across studies with case definitions, comparison groups, timing and assay methods. Direction of change reflects the predominant finding in the cited source and does not establish a diagnostic threshold. Discuss any test result with a qualified clinician.